Effect of Herbicides and Intercultivation on Weed Biomass and Canola Yield.

Canola has potentiality as a major winter crop in the southeastern United States because of its adaptability; however, weeds are one of the major constraints in its production causing loss upto 50 percent in yield. Field studies were conducted during 2005 and 2006 to evaluate the effect of intercultivation, herbicides application and their interaction on plant density, weed density, weed biomass and canola yield. Therefore, three experiments were conducted to meet the objectives. Each treatment was replicated 4 times in Randomized Complete Block Design. Results showed that weed control treatments significantly affected on plant density, weed density, weed biomass and canola yield. Trifluralin applied as pre-emergence @ 1 lt ai /ha gave 79% less weed biomass whereas 48% and 20% higher yield in 2005 and in 2006 than weedy. Likewise, Mid March intercultivation alone gave 64% less weed biomass whereas 122% and 20% higher yield in 2005 and 2006 respectively than weedy. Likewise, Trifluralin at 1 lit ai /ha in combination with intercultivation in mid march gave 200% less weed biomass than weedy whereas 187% and 59% higher yield of canola obtained in 2005 and in 2006 than weedy.